<?php
$arr = [
    ["name" => 'mortal', "fruit" => "peach", "fruit2" => "pear"],
    ["name" => 'lanting', "fruit" => "peach", "fruit2" => "watermelon"],
    ["name" => 'mortal', "fruit" => "peach", "fruit2" => "mango"],
];
$names = array_column($arr, 'name');
echo "<pre>";
print_r($names);
echo "</pre>";
//['mortal','lanting','mortal']

